TrialNet is testing a low dose of the immunotherapy drug anti-thymocyte globulin (ATG) to see if it can delay or prevent type 1 diabetes (T1D) in people ages 12 up to 35 who have a 50% risk of clinical diagnosis (Stage 3) within 2 years. Risk is defined by having two or more autoantibodies and abnormal blood sugar (Stage 2), plus at least one high-risk marker (based on test results). In an earlier TrialNet study for people newly diagnosed with T1D, low-dose ATG preserved insulin production and improved blood sugar control for 2 years. Details